To render images at interactive framerates, engines have to approximate the behavior of real world phenomena – such as shadows – rather than simulating them.
Joe Davis leads the PowerVR Graphics developer support team. He and his team support a wide variety of graphics developers including those writing games, middleware, UIs, navigation systems, operating systems and web browsers. Joe regularly attends and presents at developer conferences to help graphics developers get the most out of PowerVR GPUs. You can follow him on Twitter @joedavisdev.